JPS60135616U

JPS60135616U - Karman airflow sensor signal processing circuit

Info

Publication number: JPS60135616U
Application number: JP2321184U
Authority: JP
Inventors: 正記光安; 弘一加納
Original assignee: トヨタ自動車株式会社
Priority date: 1984-02-21
Filing date: 1984-02-21
Publication date: 1985-09-09

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of the drawing]

第１図は、自動車用エンンンに配設された、従来のカル
マンエアフローセンサの構成を示ス縦断面図、第２図は
、第１図の■−■線に沿う拡大横断面図、第３図は、本
考案に係るカルマンエアフローセンサの信号処理回路の
実施例の構成を示す、一部ブロック線図を含む回路図、
第４図は、前記実施例で用いられている発光量制御回路
の具体的構成を示す回路図である。２０・・・カルマンエアフローセンサボディ、２２・・
・カルマン渦発生体、２４・・・振動板、２６・・・信
号処理回路、２８・・・発光素子、３０・・・受光素子
、３２・・・比較回路、４０・・・ＣＲ積分回路、４２
・・・発光量制御回路、４４・・・急速充電回路、Ｄｌ
・・・発光ダイオード、ＴＲ１・・・フォトトランジス
タ、ＳＴＡ・・・スタータスイッチ。第１図第−２図Fig. 1 is a vertical cross-sectional view showing the configuration of a conventional Karman air flow sensor installed in an automobile engine, Fig. 2 is an enlarged cross-sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is an enlarged cross-sectional view taken along the line The figure is a circuit diagram including a partial block diagram showing the configuration of an embodiment of a signal processing circuit of a Karman air flow sensor according to the present invention;
FIG. 4 is a circuit diagram showing a specific configuration of the light emission amount control circuit used in the embodiment. 20...Karman air flow sensor body, 22...
- Karman vortex generator, 24... Vibration plate, 26... Signal processing circuit, 28... Light emitting element, 30... Light receiving element, 32... Comparison circuit, 40... CR integration circuit, 42
...Emission amount control circuit, 44...Quick charging circuit, Dl
...Light emitting diode, TR1...Phototransistor, STA...Starter switch. Figure 1 - Figure 2

Claims

[Claims for Utility Model Registration] A Karman vortex generator disposed in a measurement flow path, which is periodically displaced by pressure fluctuations or flow velocity fluctuations that alternately occur near both sides of the Karman vortex generator. a vibrating body,
A light emitting element that irradiates light to the vibrating body, a light receiving element that converts periodic changes in the amount of reflected or transmitted light due to displacement of the vibrating body into an analog signal, and comparing the output of the light receiving element with a threshold level, A signal processing circuit for a Karman airflow sensor comprising a comparison circuit for converting into a digital signal proportional to the air flow rate, and a CR integration circuit for detecting an average value by integrating the analog signal of the output of the light receiving element; a light emission amount control circuit that feedback controls the amount of electricity supplied to the light emitting element so that the average value of the analog signal is constant; and a capacitor of the CR integration circuit when starting the engine;
1. A signal processing circuit for a Karman airflow sensor, characterized in that a quick charging circuit for rapidly charging with a time constant shorter than the time constant of the CR integration circuit is provided.